Abstract: A system and method for constructing an airship hull is described, comprising a plurality of flexible members disposed lengthwise about the perimeter of the airship skin. The flexible members can be held in place in sleeves on the skin of the airship. The ends of the flexible members are drawn toward one another by tensioning means, causing the members to bow outwardly from a central axis and providing a rigid structure for the skin.

Abstract: A system and method for constructing an airship hull is described, comprising a plurality of flexible members disposed lengthwise about the perimeter of the airship skin. The flexible members can be held in place in sleeves on the skin of the airship. The ends of the flexible members are drawn toward one another by tensioning means, causing the members to bow outwardly from a central axis and providing a rigid structure for the skin.

Abstract: A system for backpacks that allows the backpack to be worn comfortably without shoulder straps. This is accomplished with a pair of generally triangular shaped flaps that are attached to the pack at symmetrical locations, typically the front or rear corners. The free edges of the flaps approximate catenary curves. Adjustable-length straps connect the apex of each flap to the backpack waistbelt. The flaps distribute tension relatively evenly along a substantial portion of the height of the packbag or frame, which pulls the packbag more tightly against the wearer's back, so that it can be worn comfortably without shoulder straps. The system may also be used with shoulder straps in order to lessen the stress on the user's shoulders.